diff --git a/problems/array-partition-i/array_partition_i.go b/problems/array-partition-i/array_partition_i.go
index 84f23947e..de5fcaa78 100644
--- a/problems/array-partition-i/array_partition_i.go
+++ b/problems/array-partition-i/array_partition_i.go
@@ -1 +1,14 @@
 package array_partition_i
+
+import "sort"
+
+func arrayPairSum(nums []int) int {
+	sum := 0
+	sort.Ints(nums)
+	for i, v := range nums {
+		if i&1 == 0 {
+			sum += v
+		}
+	}
+	return sum
+}
diff --git a/problems/array-partition-i/array_partition_i_test.go b/problems/array-partition-i/array_partition_i_test.go
index 84f23947e..6dd5b22c2 100644
--- a/problems/array-partition-i/array_partition_i_test.go
+++ b/problems/array-partition-i/array_partition_i_test.go
@@ -1 +1,23 @@
 package array_partition_i
+
+import "testing"
+
+type caseType struct {
+	input    []int
+	expected int
+}
+
+func TestArrayPairSum(t *testing.T) {
+	tests := [...]caseType{
+		{
+			input:    []int{1, 4, 3, 2},
+			expected: 4,
+		},
+	}
+	for _, tc := range tests {
+		output := arrayPairSum(tc.input)
+		if output != tc.expected {
+			t.Fatalf("input: %v, output: %v, expected: %v", tc.input, output, tc.expected)
+		}
+	}
+}